Reaming

Orval Fairbairn wrote in
news
In article ,
Fortunat1 wrote:

Another stupid question!

Been reaming holes in a few 4130 plates. The reamer worked fine for
about 20 holes and then the holes started getting a bit smaller to
the point the bolts got a bit snug.
In my ignorance I thought this one hand reamer would pretty much last
me the whole project, but it's obvious I'm going to need a half a
dozen of them at least just to do the wing hardware.
I did a bit of searching on the net and found some info on reamers.
All hand reamers seem to be HSS which would put me back in the same
boat I'm already in so I was tempted by the carbide reamers I saw for
sale. So, my question is; can you use a carbide tipped reamer
designed for use in a lath in a simple drill press effectively? Or,
for that matter, can you use a reamer designed for use in a lathe as
a hand reamer? Or am I just barking up the wrong tree altogether?

By the way, just for info, the holes I've beenreaming are 5/16 and
1/4. The material is .090 4130 and the holes were all laser cut about
1/64 undersize. I would ream the first hole in each plate and then
clamp together the plates in pairs to ensure accurate alignment of
the holes in each pair of plates.
Just in case it's not the reamer's fault at all!

Did you use cutting oil? Even plain old lubricating oil helps a lot
and keeps the tool cool.

Just 3in1. It didn't seem to generate a lot of heat. I was only using a
hand drive on it. I'll try a good grade of cutting oil instead next time.

Thanks!